In order to investigate the effect of nuclear factor E2 related factor (Nrf2) gene on bovine endometrial epithelial cells,this experiment used small interference RNA (siRNA) technology and tert-butylhydroquinone(tBHQ) as Nrf2 activator to study the effects of Nrf2 on the expression of hemeoxygenase-1 (HO-1) and Homebox A10 (HOXA10) in bovine endometrial epithelial cells.The results showed that in the designed two siRNA sequences(siRNA-1209 and siRNA-1672),the siRNA-1672 had a better inhibitory effect at a final concentration of 75 nmol/L and a response time of 24 h by Real-time quantitative PCR,the inhibition efficiency was over 80%.Western blotting results showed that the protein expression level of Nrf2 extremely significantly decreased at 96 h after transfection (P<0.01);While the mRNA expression levels of HO-1 and HOXA10 extremely significantly decreased by 60% and 70% (P<0.01),respectively,and the protein expression of HO-1 and HOXA10 extremely significantly or significantly decreased after 96 h (P<0.01;P<0.05).In addition,CCK8 method was used in this test,it found that the proliferation ability of bovine endometrial epithelial cells was weakened.In the tBHQ-activated the expression of Nrf2 assay,the protein expression of Nrf2 was the highest in the final concentration of tBHQ at 30 μmol/L,which was extremely significantly higher than that of control group (P<0.01),and the protein expression levels of HO-1 and HOXA10 were also higher than that of control group.This experiment results indicated that the designed siRNA-1672 could specifically inhibit the expression of Nrf2 in bovine endometrial epithelial cells,while the inhibition of Nrf2 expression led to a decrease in the proliferation ability of bovine endometrial epithelial cells,and Nrf2 regulated the expression of HO-1 and HOXA10 genes in bovine endometrial epithelial cells.

In this study,the complete CDS of 3-oxoacid CoA-transferase 1 (OXCT1) gene in Binglangjiang buffalo was amplified by PCR method,and the gene functional bioinformatics and tissue differential expression were analyzed.Specific primers were designed by Primer Premier 5.0 according the sequence of Bos taurus OXCT1 gene in GenBank (accession No.:XM_006076397),genomic DNA was extracted from Binglangjiang buffalo as template,the mRNA sequence of buffalo OXCT1 gene was amplified by PCR,the amplification products were sequenced and identified by open reading frame (ORF) with ORF Finder software,and then obtained complete sequence of OXCT1 gene CDS in buffalo which was analyzed by bioinformatics.The results showed that the length of OXCT1 gene CDS was 1 563 bp which encoded 520 amino acids,and the protein molecular formula was C₂₅₀₉H₄₀₄₁N₆₈₇O₇₄₆S₂₃,the molecular weight was 56.50 ku,the theory isoelectric point (pI) was 8.69,the instability coefficient was 27.49,the grand average of hydropathicity was -0.097,and the OXCT1 was the weak hydrophilic protein.The OXCT1 protein had no signal peptide and transmembrane structure,so it belonged to mitochondrial membrane protein.Buffalo OXCT1 contained two conserved domains which named as pcaJ_scoB_fam and AtoD.The homology of OXCT1 amino acid sequences was ≥ 97% between buffalo and other species such as cattle,Tibetan antelope,etc.The expression profile of buffalo OXCT1 gene in 13 tissues was assayed in the stages of lactation and non-lactation.The results showed that the expression level of OXCT1 gene was the highest in mammary gland,but it was not expressed in kidney,pituitary,fat,brain,skin and muscle in lactation.In non-lactating stage,the OXCT1 gene was found to express in all tissues except fat.The OXCT1 gene had the highest expression level of mammary gland in buffalo lactating,which suggested that OXCT1 gene might be associated with the regulation of milk fat synthesis.The results would provide a basis to further understanding about the anabolism and regulation mechanism of milk fat.

The aim of this experiment was to analyze the genetic structure of TCHH gene in Tan sheep and test the expression pattern of the gene in different tissues of the same month and skin tissue of different months.The full length of the coding sequence (CDS) region of TCHH gene was obtained by homologous cloning of genes,and the homology of the sequence,the basic properties of the protein and the characteristics of the repeat sequence were analyzed by bioinformatics technology.At the same time,the expression pattern of the gene in skin tissue was analyzed by semi-quantitative RT-PCR and Real-time PCR.The results showed that the TCHH gene CDS region was 4 425 bp in length and contained two repeats,encoding a total of 1 474 amino acids.The TCHH amino acid sequence of Tan sheep was highly homologous within the species,with 96.3% homology with Capra hircus,and the homology between species was poor.The homology with Homo sapiens and Mus musculus was 48.4% and 40.5%,respectively.The molecular formula of TCHH protein was C₈₀₀₆H₁₃₁₈₇N₂₇₈₇O₂₆₆₁S₆,the molecular mass was 191.26 ku,and the theoretical isoelectric point was 5.76,which was a hydrophilic protein.Its protein instability index was 119.37,and its stability was poor.The amino acid of this protein contained two conserved regions,S-100 calcium binding domain and protein kinase domain,which were rich in α-helix,up to 89.89%.It was speculated that the secondary structure was a long rod-like molecular structure.The results of tissue expression profiling showed that the gene was specifically expressed in skin tissue,and its mRNA expression decreased with the increase of the age of Tan sheep,which was consistent with the growth trend of the hair curling trait of Tan sheep wool.The specific structure and expression pattern of the TCHH gene indicated that this gene played an important role in the hair curling trait of Tan sheep.This study would provide important reference for the study of the biological mechanism of the occurrence of Tan sheep wool.

This study was aimed to clone cell death-inducing DNA fragmentation factor 45-like effector A (CIDEa),analyze the sequences by bioinformatics software,and detect the expression of CIDEa gene in different tissues of Yuxi fat-tailed sheep.Using RNA of the adipose tissue in Yuxi fat-tailed sheep as a template,the complete CDS sequence of CIDEa gene in Yuxi fat-tailed sheep was amplified and cloned,and the sequencing result was analyzed by bioinformatics.The expression of CIDEa gene in heart,liver,lung,spleen,kidney,rumen,small intestine,longissimus dorsal muscle,subcutaneous adipose and visceral adipose tissue of Yuxi fat-tailed sheep were analyzed.The results showed that the length of CDS sequence of CIDEa gene in Yuxi fat-tailed sheep was 660 bp and encoded 219 amino acids.The homology of CIDEa gene in Yuxi fat-tailed sheep were 99.1%,96.8%,96.2%,98.8%,85.0% and 79.4% with Ovis aries,Bubalus bubalis,Bos taurus,Pantholops hodgsonii,Sus scrofa and Homo sapiens,respectively.The physical and chemical properties of CIDEa protein showed that the molecular weight was 24.38 ku and the theoretical isoelectric point (pI) was 9.12,which belonged to alkaline protein.There was no transmembrane structure and signal peptide in CIDEa protein.The subcellular localization results showed that CIDEa protein was located in the cytoplasm (47.8%),mitochondria (26.1%),nuclear (17.4%),vacuolar (4.3%) and endoplasmic reticulum (4.3%).The tertiary structure of CIDEa protein mainly consisted of 2 alpha helices,4 beta foldings and random coils.Real-time quantitative PCR results showed that the expression of CIDEa gene in subcutaneous adipose and visceral adipose were obviously higher than other tissues,which followed by intestine,liver,spleen,rumen,heart,kidney,lung and longissimus dorsi muscle ranged from high to low.This results provided basic data for further study on the function of CIDEa gene in lipid metabolism and regulation of mutton quality in sheep.

The aim of this study was to clone and analyze Myf6 gene in yaks by bioinformatics,and investigate its expression in different periods.The snowy yak in Qinghai was taken as the research object.The Myf6 gene CDS region was cloned and sequenced by designing primers,and its functional structure was predicted by bioinformatics software.The results showed that the yak Myf6 gene contained a 729 bp open reading frame (ORF) encoding 242 amino acids.The results of homology alignment and phylogenetic tree analysis indicated that the amino acid sequence of yak Myf6 was close to common cattle and sheep.The physicochemical properties of Myf6 protein were predicted and analyzed.The structural formula of Myf6 protein was C₁₁₆₇H₁₈₇₀N₃₃₆O₃₇₂S₁₃,and the theoretical isoelectric point was 5.64,with serine being the highest,followed by leucine,glutamic acid,proline and arginine.The hydrophobic average was -0.586,the most hydrophilic was -2.467,and the hydrophobicity was 1.511.It was predicted that the yak Myf6 was predicted to be hydrophilic and soluble protein.There were portions that could form coiled coil;The phosphorylation sites results showed that there were 26 serine kinases,10 threonine kinases and 5 tyrosine kinases;Subcellular localization analysis showed that the encoded product was most distributed in the nucleus (73.9%),followed by cytoskeleton (13.0%),cytoplasm (4.3%),Golgi apparatus (4.3%) and secretory system vesicles (4.3%).The protein secondary structure was predicted to consist mainly of random coils (49.17%),followed by alpha helix (33.47%),extended chain (11.57%) and beta-sheet (5.79%).Functional analysis of the protein showed that the growth factor function had a higher probability (7.694),followed by transcriptional regulation,which was predicted to participate in the biological regulation of the body as a growth factor.The results of Real-time PCR showed that Myf6 gene was expressed in the longissimus dorsi muscle of fetal calf,6 months old and 4 to 5 years old,and the expression level at 6 months old was significantly higher than that of fetal cattle and 4 to 5 years old (P<0.05).The above results provided important research data for the study of yak Myf6 myogenic factors,and provided a reference for improving the economic traits of yak.

Glucagon-like peptide-2(GLP-2) is a short peptide consisting of 33 amino acid residues and mainly secreted by L endocrine cells located in the small intestine edge and colon.GLP-2 can binds to its receptor GLP-2R to activate a series of downstream reactions to achieve its functions.It can promote intestinal growth and development,repair of damaged intestine,accelerate nutrient transport and absorption,and enhance intestinal mucosal barrier function.At present,GLP-2 and[Gly-2] GLP-2 have been approved for the treatment of human intestinal mucosal injury diseases such as short bowel syndrome.In addition,GLP-2 has a wide range of applications in livestock production because of its many functions.For example,GLP-2 can be used in the treatment of some common gastrointestinal inflammatory diseases in livestock.It can also alleviate lung injury caused by bovine sepsis and play an important role in maintaining liver health.Besides,as an anorexia signal peptide,GLP-2 can increases the conversion rate of food in livestock.GLP-2 is also used to relieve adverse environmental stress caused by changes in the surrounding environment,such as heat stress,water deficiency stress,fluorosis and intestinal dysfunction during diet switching and so on,In this paper,the latest research progress of GLP-2 and its application in animal production are discussed.

In order to understand the adaptation mechanism of Tarim Red deer to low quality roughage and promote more scientific and effective utilization of roughage to improve the economic benefit of Tarim Red deer breeding,the effect of feed energy to nitrogen ratio on rumen fermentation was studied.Based on the experimental results of the degradation characteristics of feed raw materials (effective degradation rate of organic matter and crude protein) by rumen nylon bag method,eight experimental diets with different gradients of energy nitrogen release (RDN/DOM=15 to RDN/DOM=29) at the same nutritional level were designed as fermentation substrates.The pH and ammonia nitrogen (NH₃-N) of fermentation products and total volatile fatty acid (TVFA) content and microbial protein (MCP) content were measured and compared by in vitro digestion test.The results showed that when RDN/DOM=19 compound feed was used as culture substrate to produce gas in vitro,the MCP production at 12 h was significant higher than that at other time points (P<0.05).Therefore,the culture time was determined as 12 h.When RDN/DOM was 23,the concentration of NH₃-N in culture medium was the lowest (8.34 mg/dL),the MCP production (11.76 mg/dL),TVFA content (71.24 mmol/dL) and acetic acid/propionic acid (2.79) were highest.Therefore,the optimum RDN/DOM of Tarim Red deer was 23 under the experiment condition,which provided an important basis for the follow-up study of synchronization index (SI) of energy and nitrogen release in the diet of Tarim Red deer.It also provided data supporting for further study of nitrogen metabolism of Tarim Red deer.

The aim of this study was to investigate correlation between body weight and body sizes of F1 hybrid of Lanzhou Fat-tailed sheep×Small-tailed Han sheep,which could provide scientific theory basis for estimation of weight through its body sizes.In the experiment,80 F1 hybrids of Lanzhou Fat-tailed sheep×Small-tailed Han sheep with 40 lambs of each sex at 150 days of age were selected randomly as objects.The body weight (Y),body length (X₁),body height (X₂),chest circumference (X₃),cannon circumference (X₄),chest depth (X₅),chest width (X₆) of lambs were measured.The phenotypic correlation analysis,path analysis,stepwise linear regression analysis and subdivision of correlation coefficients between the body weight and body sizes of rams and ewes were performed using SPSS 22.0 software.The results indicated that there were extremely significant positive correlations between body length,body height,chest circumference,cannon circumference,chest depth,chest width and body weight of F1 hybrid of Lanzhou Fat-tailed sheep×Small-tailed Han sheep (P<0.01).The correlation degree between chest circumference and body weight was the highest,the correlation coefficients were 0.907 and 0.908 in rams and ewes,respectively.The correlation degree between body length and body weight was followed whose correlation coefficient of rams was 0.875,and that of ewes was 0.844.Extremely significant positive correlations were also found among body sizes traits (P<0.01),in which,the correlation coefficient between chest circumference and body length was the highest.Chest circumference and body length mainly had an effect on body weight by direct action,while chest depth,cannon circumference,body height and chest width mainly affected body weight through indirect effect.The direct impact of chest circumference on body weight was the greatest and the indirect influence of chest depth on body weight was the highest.The optimal regression equation between the body weight and body sizes of rams and ewes were Y=-43.861+0.675X₃+0.394X₁(r=0.945,P<0.01),Y=-38.378+0.590X₃+0.397X₁(r=0.948,P<0.01).In conclusion,chest circumference and body length were two important factors influencing body weight of F1 hybrid of Lanzhou Fat-tailed sheep×Small-tailed Han sheep.In the process of breeding and fattening,the choice of chest circumference and body length should be strengthened while the influence of chest depth,cannon circumference,body height and chest width also should be considered.

The purpose of this study was to investigate the effects of compound Chinese herbal medicine supplements on growth performance,nutrient apparent digestibility and blood parameters of finishing pigs.The 192 healthy and DYL crossbred finishing pigs with (56.21±1.76) kg body weight of 130 days old were selected and divided into 4 groups with 4 replicates per group and 12 heads per replicate according to the principle of similar body weight and the same proportion of males and females.The levels of compound Chinese herbal medicine in the diets of 4 groups were 0 (control group),650,1 000 and 1 500 mg/kg,respectively.The trial was divided into pre-feeding period (7 d) and formal period (30 d),and growth performance,nutrient apparent digestibility,biochemical indexes,antioxidant indexes and immune indexes in blood of finishing pigs were determined.The results showed that:①Compared with the control group,the 650 mg/kg group could increase the average daily gain and decrease the F/G to some extent (P>0.05).②After adding 650 and 1 500 mg/kg of compound Chinese herbal medicine to the diet,the apparent digestibility of CP was significantly higher than that of the control group (P<0.05),and the apparent digestibility of NDF,ADF,Ca,P did not show difference among the groups (P>0.05).③The addition of 650 mg/kg compound Chinese herbal medicine in the diet significantly increased the serum HDL-C level and GSH-Px activity of finishing pigs (P<0.05),and significantly decreased the serum LDL-C level and MDA content (P<0.05).④The addition of compound Chinese herbal medicine to the diet had no significant effect on the body's immune indexes (P>0.05).In summary,the addition of 650 mg/kg compound Chinese herbal medicine to the diet had a positive effect on the growth performance and nutrient apparent digestibility of finishing pigs,which could improve the blood biochemical indexes of finishing pigs,reduce the content of serum MDA and increase the GSH-Px activity.

This experiment was conducted to investigate the effects of combinations of tannin and zinc oxide on fecal microbiota,serum immunity,antioxidation and liver function-related blood biochemical parameters in weaned piglets.Two hundred and seventy weaned piglets of Duroc×Landrace×Yorkshire on 25-day-old with similar body weight were randomly divided into nine groups with three replicates per group and ten pigs per replicate.Piglets in the control group were fed a basal diet supplemented with 3 000 mg/kg zinc oxide.Piglets in experimental groups 1 to 8(T1-T8) were fed basal diets added with following combinations of zinc oxide and tannin:(2 000+0),(2 000+1 000),(1 000+0),(1 000+1 000),(1 000+1 500),(1 000+2 000),(0+1 500) and (0+2 000) mg/kg,respectively.The trial lasted for 30 d.Fresh feces samples of piglets were collected on the 14th and 28th day of the trial to determine the number of 3 pathogenic bacteria in the feces.Blood samples were taken at the end of the experiment to determine immunity,antioxidant and liver function indexes in serum.The results showed that there were no significant differences in the numbers of E.coli,Lactobacillus and Bacillus bifidus in feces of piglets among each group on the 14th day of the trial (P>0.05).On the 28th day of the trial,the numbers of Lactobacillus in feces of piglets in groups T1 and T6 were extremely significantly higher than that in the control group (P<0.01),and the numbers of Bacillus bifidus in feces of piglets in groups T1 and T6 were significantly higher than that in the control group (P<0.05).However,there was no significant difference in the number of E.coli between each group (P>0.05).There were no significant differences in serum IgG and IgA content,MDA content and GSH-Px activity between each group (P>0.05).However,GSH content in serum in groups T5,T6,T7,T8 were extremely significantly higher than that in the control group (P<0.01).Except for the T2 and T5 groups,AST activity in serum of the other groups was significantly or extremely significantly lower than that of the high zinc control group (P<0.05;P<0.01).This test showed that compared with the single use of high dose zinc oxide,the appropriate combination of tannin and zinc oxide was beneficial to Lactobacillus and Bacillus bifidus proliferation,antioxidant capacity improvement of the body and liver protection in weaned piglets.

This experiment was conducted to investigate the effects of compound preparations of protease and probiotics on production performance and somatic cell count of dairy cows.240 dairy cows with similar age,parity,lactation day and physiological trait were randomly assigned to 4 groups with each group 6 replicates,10 dairy cows per replicate.Control group was fed basal diet,groups Ⅰ,Ⅱ and Ⅲ were added 0.5,1.0 and 1.5 kg/t of compound preparations of protease and probiotics in the basal diet,respectively.The pre-test period was 10 d,and the test period was 40 d.Cow feces were collected at 10th,20th,30th,and 40th day,and the composition of cow feces was analyzed by fecal analysis sieve.Milk samples were collected on the 1st,20th and 40th day of the experiment.The milk fat rate,milk protein rate,non-fat solids and somatic cells (SCC) in milk were measured by milk analyzer.The average daily milk yield (ADMY) and average daily feed intake (ADFI) of each cow was recorded during the test.The results indicated that compound preparation of protease and probiotics groups could significantly increase the cow milk yield (P<0.05) and the protein and fat content in milk (P<0.05),decrease somatic cell counts (P<0.05),improve feces structure.In conclusion,the optimum adding amount of compound preparations of protease and probiotics was 1.0 kg/t,it could improve the milk quality and reduce the number of somatic cells in dairy cows.

The study was carried out to evaluate the effects of excess vitamin A (VA) on biochemical indexes of bone formation and the relative expression of alkaline phoshatase (ALP) and bone gla-protein (BGP) mRNA in small intestine,tibia and liver of broilers during early growth,and provide theoretical basis for further demonstrating the negative effects of excessive VA on calcium and phosphorus deposition in broiler chickens.The completely randomized design was used in this experiment.225 male and 225 female one-day-old AA broilers with similar body weight were divided into five treatment groups with six replicates of fifteen chicks each.The broilers were fed the basal diets supplemented with 3 000,6 000,15 000,30 000 or 60 000 IU/kg VA,respectively.The trial lasted for 28 d.At the age of 14,28 d,one bird from each replicate of each treatment was randomly selected and blood sample was obtained from the wing vein.The same birds used to obtain blood samples were killed,and liver,duodenum,jejunum,ileum and tibia samples were quickly removed and stored at -80℃.The regression analysis results showed that the contents of BGP,activities of ALP and BAP in serum,the relative expressions of ALP and BGP mRNA in the tibia,liver and small intestine of broilers during early growth significantly decreased (P<0.05) or tended to significantly decrease (P<0.10) linearly or quadratically with the increase of dietary VA.And the relative expressions of ALP mRNA in the tibia and liver and the relative expressions of BGP mRNA in the liver of broilers on the day 14 of experiment,ALP activity in serum and the relative expressions of ALP mRNA in the liver and the relative expressions of BGP mRNA in the tibia and ileum of broilers on the day 28 of experiment were the lowest when VA supplemental level was 42 766 to 47 185 IU/kg.These results implied that the dietary VA could reduce the serum BAP activity of broilers during early growth in linear and regulated the contents of BGP and ALP activity in serum,the relative expressions of the ALP and BGP mRNA in the tibia,liver and small intestine of broilers in a dose-dependent manner during early growth,and diets supplemented with 42 766 to 47 185 IU/kg VA had stronger inhibition effect on above indexes.These results implied that excess VA suppressed biochemical markers of bone formation and reduced the ALP and BGP mRNA in the tibia,liver and small intestine of broilers during early growth.

The aim of the experiment was to compare the effects of adding tannins and feed cellulose on the growth performance,blood biochemical parameters,slaughter performance and organ development of Hu sheep.A total of 72 male Hu sheep with good growth and average body weight (18.36±1.65) kg at 3 months were randomly divided into control group (CK) and 3 treatment groups (groups T,FC and M),with 18 Hu sheep in each group.Group CK was fed a basal diet,and group T was fed a basal diet added with 0.1% tannin,group FC was added with 0.1% feed cellulose,and group M was added with 0.1% tannin +0.1% feed cellulose in the basal diet.The trial lasted 94 days,including 7 days of transition,7 days of pre-feeding period,and 80 days of the trial period.The results showed that:① The final body weight and average daily weight gain (ADG) of groups FC and M of Hu sheep was significantly higher than that of group CK (P<0.05).F/G in group CF was lower than that of group CK.There was no significant difference in average daily feed intake (ADFI) among all the groups (P>0.05).②Compared to group CK,the ratio of white ball was significantly lower (P<0.05),and the contents of globulin,total protein and the activity of alkaline phosphatase were significantly higher (P<0.05) in groups T,FC and M.There was no significant difference in albumin,total cholesterol,triglycerides,alanine aminotransferase and glucose among all the groups (P>0.05).③The live weight before slaughter (SBW) of Hu sheep in group FC was significantly higher than that in group CK (P<0.05).The carcass weights in groups FC and M was significantly higher than that in group CK (P<0.05).The slaughter rate of Hu sheep in group M was significantly higher than that of group CK (P<0.05).The thickness of backfat in group T was significantly lower than that of group CK (P<0.05).The GR value of groups FC and M of Hu sheep was significantly higher than that in group CK (P<0.05).There was no significant differences in net meat rate,flesh-to-meat ratio and lion eye area among the groups (P>0.05).④ The hoof weights in groups T,FC and M were significant higher than that in group CK (P<0.05).There were no significant differences in head and fur,liver,lung,heart and kidney weights,hoof and internal organs indexes among all the groups (P>0.05).In conclusion,adding feed cellulose and tannin in the diet of Hu sheep could increase the average daily gain and slaughter rate,reduce the ratio of feed to meat,improve the immunity,and had no adverse effects on organ development.It provided a theoretical basis for the application of tannin and feed cellulose in ruminant culture.

This experiment was to study the etiology of zinc (Zn) deficiency in the Wumeng Semi-fine wool sheep.20 Zn-deficient Wumeng Semi-fine wool sheep were selected from Xingfa farm in Hezhang county as the experimental group,and 20 healthy Wumeng Semi-fine wool sheep were selected from Liangshuigou sheep farm in Weining county as the control group.Mineral concentrations were determined by inductively coupled plasma atomic emission spectroscopy in soil,forage and in tissue of Wumeng Semi-fine wool sheep.The blood parameters and biochemical indexes were determined on automatic hematology analyzer and biochemical kit.The results showed that Zn content in the soil and forage from the experimental pasture was extremely significantly lower than those of control area (P<0.01).Zn contents in the blood and liver in affected Wumeng Semi-fine wool sheep was extremely significantly lower than those of control group (P<0.01).There were no significant difference in other elements between two groups (P>0.05).The numbers of RBC,LY and NE in blood from affected Wumeng Semi-fine wool sheep were extremely significantly lower than those of control group (P<0.01).The levels of SOD,GSH-Px,CAT,LDH and AKP in serum from the affected Wumeng Semi-fine wool sheep were extremely significantly lower than those of control group (P<0.01).The content of MDA from affected animals were extremely significantly higher than that of control group (P<0.01),but there were no marked differences on the numbers of Hb,PCV,WBC,the content of BUN and the activities of AST,ALT and γ-GT between the two groups (P>0.05).In conclusion,the main symptoms of Wumeng Semi-fine wool sheep were "Zn deficiency" which mainly caused by low Zn content in soil and herbage.Adding proper amount of zinc sulfate in the diet could prevent and protection the disease of Wumeng Semi-fine wool sheep.

China is a big country of animal husbandry with a large demand for feed resources,but facing with serious problems such as insufficient supply.Unconventional feed resources are of great significance to the healthy and sustainable development of Yellow-feathered broilers industry.In the current review,research progresses on the effect of non-conventional feeds on growth performance and meat quality of Yellow-feathered broilers in recent decade are presented,including non-conventional energy feeds,non-conventional protein feeds and some other non-conventional feeds.The non-conventional energy feeds include rice bran,feed rice,cassava and cassava residues.Non-conventional protein feeds include cottonseed meal,rapeseed meal,distillers dried grains with soluble (DDGS) and peanut meal.Some other non-conventional feeds are mulberry leaf powder,Moringa oleifera powder,mushroom residues,fermented monosodium glutamate (MSG) residues and pomelo peel powder. etc.Toxin or some other anti-nutritional factors contained in non-conventional feeds are showed specially.In addition,advantages and disadvantages of non-conventional energy/protein feeds compared to corn and meal are demonstrated.Proper amount of nutritional characteristics and contents of non-conventional feeds,when and how long used in the diet of Yellow-feathered broilers are given out.At last,some problems existing in the utilization of non-conventional feed resources are pointed out,and some solutions and further research directions are proposed.On the basis of this review,theoretical and technical supports for the application of these non-conventional feeds in Yellow-feathered broilers are presented to further promote healthy sustainable development of Yellow-feathered broilers industry.

To study the adaptability of the introduced variety of goats in South China,the reproductive performance and disease characteristics of the Chuanzhong Black goat under barn feeding condition were statistically analyzed,which would provide data for the feasibility analysis of feeding Chuanzhong Black goat in South China.The data related to the performances of the reproduction,growth and disease of the goats were collected from 2014 to 2017,and Excel and SPSS software were used to analyze the experimental data.The results showed that the primiparous lambing rate of Chuanzhong Black goat was 181%,and the lambing rate of the pluriparous goats was 200%;The alive lambs rate and weaning survival rate were 87.2% and 83.8%,respectively;The average birth weight of male and female lambs was 2.85 and 2.75 kg,respectively;The average weaning weight was 10.15 and 9.64 kg,respectively;The parity per year was approximately 1.5.Under the barn feeding condition in South China,the reproductive performance of Chuanzhong Black goat decreased slightly compared with the animals in the original region;However,with the increase of living time and improvement of feeding condition,the reproductive of Chuanzhong Black goat gradually recovered.In the case of barn feeding environment,goats were prone to pneumonia,and were easy to abort due to illness in the late pregnancy;The mortality of lambs increased as the number of lambs born increases.In conclusion,the Chuanzhong Black goat introduced from other provinces exhibited certain adaptability problems in the short-term,but under the suitable feeding and advanced management environment,they could maintain excellent reproductive performance and the characteristic of disease resistance.Therefore,Chuanzhong Black goat were feasible to be raised under barn feeding environment in South China.

This study was aimed to clone the CDS sequence of Zfx gene in Equus asinus and analyze the sequence by bioinformatics softwares.Specific primers were designed according to the mRNA sequence of Zfx gene in Bos taurus published in GenBank (accession No.:D84097.1).The CDS sequence of Zfx gene in Equus asinus was gained by RT-PCR,and the nucleotide sequence and protein structure prediction of Zfx gene CDS in Equus asinus were analyzed.The results showed that the CDS sequence of Zfx gene in Equus asinus was 2 403 bp,encoding 800 amino acids.The nucleotide sequence homology of Zfx gene CDS sequence in Equus asinus with Equus caballus,Bos taurus,Canis lupus familiaris,Ceratotherium simum,Cervus elaphus,Feils catus,Homo sapiens,Ovis aries and Pan troglodytes were 99.6%,95.0%,95.3%,97.9%,93.5%,94.9%,95.0%,95.7% and 94.9%,respectively.Phylogenetic tree was constructed for nucleotide sequences of Zfx gene CDS in Equus asinuss and other 9 mammals,which showed that Equus asinus were closely related to Equus caballus,followed by genetic relationship with Ceratotherium simum,and they were closely related to Cants lupus familiaris and Feils catus that were in the same class,and the genetic relationship was week with Ovis aries and Bos taurus.The theoretical isoelectric point (pI) of Zfx protein was 5.19,the instability coefficient was 42.94,and the extinction coefficient was 35 810.Zfx protein belonged to unstable hydrophilic protein and non-secreted protein,contained 60 phosphorylation sites,no signal peptide and transmembrane structure.The alpha helix,extended chain and random coil of Zfx protein were 23.12%,20.25% and 56.63%,respectively,and the tertiary structure was mainly alpha helix and random coil.In this experiment,the CDS sequence of Zfx gene in Equus asinus was successfully cloned,which provided a basis for further study on the structural function of Zfx gene and its enconded protein.

This experiment was conducted to study the effects of mild fatty liver on slaughter performance and meat quality of dwarf Jingxing-Huang chickens at marketing age.At age of 98 days,273 male chickens were selected randomly from the same batch experimental population by two times,the slaughter performance,meat quality and serum biochemical indices were tested.The liver tissuees were collected for evaluating the fatty liver through HE staining and Oil Red O staining.A total number of 53 chickens,which had vacuolar degeneration,and more fat deposition were detected in the disordered liver cells,were considered as mild fatty liver group.For the rest 219 chickens,which liver cells were tightly arranged without obvious denatured feature,were considered as the control group.Compared with the control group,the results of mild fatty liver group were as follows:①The serum triglyceride,total cholesterol,and low density lipoprotein content increased extremely significantly (P<0.01),the liver weight and liver index also increased significantly or extremely significantly,respectively (P<0.05;P<0.01),the cholesterol content was positively correlated with liver weight extremely significantly (P<0.01).② Slaughter performance was improved,the live weight,dressed weight,eviscerated weight and thigh muscle weight increased significantly or extremely significantly (P<0.05;P<0.01).③ Meat quality was improved significantly,the intramuscular fat content increased extremely significantly both in breast and thigh muscle (P<0.01),the shear force decreased significantly or extremely significantly in breast and thigh muscle,respectively (P<0.05;P<0.01).For breast muscle,L^*_{45 min} and L^*_{24 h} decreased significantly (P<0.05),and the a^*_{45 min} increased extremely significantly (P<0.01),the pH_{24 h} was only 0.04 lower in mild fatty liver group,but the difference was significant (P<0.05).④ The abdominal fat deposited excessively,the weight and percent of abdominal fat increased extremely significantly (P<0.01).The above results indicate that,at the marketing age,the occurrence of mild fatty liver was accompanied by the improvement on slaughter performance and meat quality,however,it also caused excess deposition of abdominal fat.

In China pig breeding,feeding efficiency testing usually cost too much time,and the calibration formula was lack all the time.In this study,the feeding efficiency testing period of Duroc pigs and the calibration formula of residual feed intake (RFI) were analyzed to solve the problems above.The Pearson correlation programs were used to analyze RFI and NLIN programs were used to acquire the correction coefficient of RFI in Duroc pigs.The linear interpolation of different body weight RFI and the real weight RFI of 100 kg were used to fit the parameters of Duroc pigs up to 100 kg body weight RFI correction formula,and obtain RFI correction coefficient of Duroc pigs up to 100 kg body weight.The results showed that the correlation of RFI calculated by four methods at 105-180 d and whole testing period were the highest,and the correlation coefficient was above 0.92.The adaptive regression equation:Full-time RFI=0.9786×(105-108 d measurement phase RFI)+0.0002,the highest fit was 0.9734.The RFI correction factor for Duroc boars and sows up to 100 kg body weight were 0.0519 and 0.0179,respectively.Moreover,under this coefficient,the accuracy of correction in the range of 70-100 kg for boars was higher,and the correction of sows in the range of 40-100 kg was more accurate.These results could be directly used to develop breeding programs,which could reduce the RFI measurement time,provide references for more accurate calculation of RFI to develop excellent breeding programs.

This study was aimed to clone the potential promoter region of porcine SEPW1 gene and analyze its transcriptional activity,obtain its core promoter region,and analyze the effect of transcription factor SP1 on the transcriptional activity of SEPW1 gene for further studying the function of porcine SEPW1 gene in meat traits.The expression level of SEPW1 gene in Large White pigs tissues was detected by Real-time quantitative PCR,and the spatial expression profile was constructed.6 SEPW1 gene promoter deletion fragments were cloned by PCR,and 6 dual luciferase reporter vectors were constructed,the core promoter region of SEPW1 gene was obtained by detecting the dual luciferase activity of each vector;The potential transcription factor SP1 binding site was predicted through bioinformatics analysis of the core promoter region.The transcription factor SP1 binding site and its effect on the transcriptional activity of SEPW1 gene were confirmed by over-expression,down-expression,site-directed mutation and EMSA.The results showed that SEPW1 gene was widely expressed in 12 tissues of 4-month-old Large White pigs,while the expression levels were higher in castrocnemius and heart.The results of dual luciferase activity indicated that there was the core promoter region of SEPW1 gene 5'-flanking region at -443 to -231 bp,and there was a potential SP1 binding site at -378 to -306 bp.The results of over-expression and down-expression of SP1 gene indicated that transcription factor SP1 promoted the transcription of SEPW1 gene.Site-directed mutagenesis and EMSA assay confirmed that transcription factor SP1 could directly bind to SP1 binding sites (-348 to -339 bp) in the promoter region of SEPW1 gene.The results suggested that transcription factor SP1 could directly target the promoter region of SEPW1 gene and promote SEPW1 gene transcription.

Traditional surgical castration technology is being challenged by animal welfare and large-scale standardized livestock production.As an alternative to surgical castration,immuno-castration can block testicular development,control sexual behavior,and avoid the pain caused by surgery.Immuno-castration uses immunological methods to destroy the hormone balance of the hypothalamic-pituitary-gonadal axis,decrease the hormone levels of GnRH,LH,FSH,and gonadal hormone,inhibit the gonadal function,and then achieve the purpose of castration.Immuno-castration includes hormone immuno-castration and gene immuno-castration,and its targets have undergone bottom-up screening on the hypothalamic-pituitary-gonadal axis,which identified are testosterone,LH,FSH,GnRH and KISS-1.The three targets of GnRH hormone,GnRH and KISS-1 genes located upstream on the hypothalamic-pituitary-gonadal axis have better castration effects.Studies on the effect and mechanism of immuno-castration show that immuno-castration has the characteristics of improving production performance,safety and reversibility.While the reversible mechanism of immuno-castration is still unclear.Castration causes the adrenal gland to play a compensatory role,and the effect of immuno-castration on adrenal compensation has not been reported.This paper introduces the immuno-castration mechanism of targets,discusses the characteristics and application of immuno-castration,in order to provide theoretical basis for promoting the application of immuno-castration technology in the field of animal production and reproduction.

This study was aimed to analyze the conservation efficiency of Yili goose in reservation farm,and 9 microsatellite markers were used to detect the genetic diversity of three generations (0,1 and 2 generations) of Xinjiang Yili goose.In this experiment,all blood samples were took from three generations of Yili goose.DNA was extracted using phenol-chloroform extraction method,and detected by 12% polyacrylamide gel electrophoresis,silver nitrate staining and judge genotype.The results showed that a total of 78 alleles were detected in 9 microsatellite loci in three generations of Yili goose,26 alleles were detected in 0,1 and 2 generations.The average expected heterozygosity (He) of three generations were 0.4322,0.4232 and 0.4516,respectively.The average polymorphic information content (PIC) were 0.3751,0.3707 and 0.3936,respectively,it showed that three generations of Yili goose were in moderate polymorphism,the genetic variation was at a medium level,and there was no significant difference in average He and PIC among three generations (P>0.05).The genetic distances of three generations were 0.0097,0.0184 and 0.0074,respectively.In conclusion,Yili goose had rich genetic diversity,and the current conservation method adopted by the conservation farm had better preserved the original genetic diversity of Yili goose.

In order to establish an indirect ELISA (iELISA) diagnostic method for detection of camel parabronemosis,in this experiment,the CPR gene of cysteine protease was recombinant expression,and the obtained recombinant protein (rCPR) was purified and detected by Western blotting.Using the purified recombinant protein as an antigen,the conditions of coating antigen,coating conditions,antibody dilution,dilution of enzyme-labeled secondary antibody,blocking solution and blocking time were optimized by checkerboard titration test,and the iELISA diagnostic method for detection of Parabronema skrjabini was established.Repeated,sensitive,specific and clinical tests were performed on the established iELISA assay.The results showed that the optimal coating concentration of the antigen was 8 μg/well,the optimal dilution of the serum and the enzyme-labeled secondary antibody were 1:50 and 1:5 000,respectively,and the optimal coating condition was 4℃ overnight.The optimal blocking condition was 3% BSA for 2 h.The cut-off value was 0.235,and the serum D_{450 nm} value>0.235 was determined to be positive.The coefficient of variation in the repeatability test was <10%,and the repeatability was good;The sensitivity of detecting positive serum by this method was 96.3%;This method only specifically reacted with the positive serum of Parabronema skrjabini,and did not cross-react with other parasite-positive sera,the specificity was 100%;140 clinical sera were tested and the positive rate was 86.4%.In summary,this experiment successfully established an iELISA method for rapid and effective diagnosis of camel parabronemosis.

This study was aimed to investigate the expression of porcine adenovirus type 3 (PADV3) Protease protein in Escherichia coli (E.coli),and prepare the polyclonal antibody of Protease protein.PADV3 Protease gene was amplified by PCR,the recombinant prokaryotic expression vector pET28a-PADV3-Protease and eukaryotic expression vector pEGFP-PADV3-Protease were constructed and identified by double enzyme digestion and sequencing.The recombinant prokaryotic expression vector pET28a-PADV3-Protease was transformed into E.coli BL21(DE3),the positive recombinant prokaryotic expression strain was induced by IPTG,and identified by SDS-PAGE and Western blotting.The recombinant Protease protein was purified and emulsified with adjuvant to prepare the immunogen which was innoculated into rabbit to prepare a polyclonal antibody against Protease protein.The eukaryotic expression vector pEGFP-PADV3-Protease was transfected into HEK293 cells and the EGFP-protease fusion protein expression stable cell line was screened by G418.The immunological activity and antibody titer of the antibody were detected by immunoperoxidase monolayer staining (IPMA) base on the fusion protein expression stable cell line.The results showed that the length of Protease gene open reading frame (ORF) was 615 bp.Western blotting analysis result showed that Protease protein in the prokaryotic expression system existed as an inclusion body with a molecular weight of 23 ku which was similar to Protease protein expressed in eukaryotic cells.In the fusion protein expression stable cell line,Protease was distributed in both the nucleus and cytoplasm.The Protease specific polyclonal antibody specifically reacted with the EGFP-Protease fusion protein expression stable cell line.The Protease prokaryotic expression strain and the eukaryotic expression cell line were successfully constructed,the PADV3-Protease protein polyclonal antibody was prepared and there was wonderful immunoactivity,providing basic materials for further study of the biological function of Protease protein and the serological diagnostic of PADV3.

To prepare monoclonal antibodies (MAb) against Mycobacterial acid resistance protease (MarP) of Mycobacterium bovis (M.bovis),the cytoplasmic domain of MarP were expressed with Escherichia coli (E.coli) expression system.The serine proteinase activity of MarP were detected using β-casein and DTT as substrate and inhibitor,respectively.The mice were immunized with the active MarP protein,and the spleen cells were fused with SP2/0 cells,and mixed with the feeder cells.The cells were gently shaken and dispensed into a 96-well culture plate,and cultured in 37℃,5% CO₂.On the 10th day,the positive cell were screened by IFA and indirect ELISA for subcloning.Finally,the hybridoma cell lines which secreted monoclonal antibodies against MarP were prepared.The reactivity of monoclonal antibodies with recombinant expressed MarP and natural MarP protein was detected by Western blotting and ELISA.The results showed that the recombinant MarP had good serine proteinase activity,and could digeste 30 μg β-casein completely in 12 h.In addition,DTT could inhibit the activity of MarP.Five MAbs against MarP were obtained from the mice that immunized by MarP protein,and all these five antibodies could recognize the liner epitopes of recombinant MarP and natural MarP.The antibodies didn't react with proteins from E.coli and M.smegmatis.The purified MarP protein and MAbs against MarP provided tools for further studies on the screening substrate of MarP and the mechanism of MarP in the resistance to acid stress of M.bovis.

In order to clarify the characteristics of the porcine epidemic diarrhea virus (PEDV) mutant strain in Shandong,Vero cells were used for virus isolation and in vitro subculture of diarrhea materials from a pig farm in Juxian.The virus sequence and characteristic analysis were performed by optical microscopy and ultrathin section observation,RT-PCR detection,indirect immunofluorescence assay,S gene sequence evolution analysis,titer determination and pathogenicity test,and explored the change of cell shedding time after poisoning.Optical microscopy showed that the virus infected with Vero cells could cause typical syncytium lesions.Ultrathin sections of the cells showed that the virions were mostly dense cores,which caused the mitochondria of the host cells to swell and dissolve.The results of RT-PCR and indirect immunofluorescence assay confirmed that the isolated virus of JX16 belonged to PEDV.The strain was finally confirmed to be a variant strain by sequencing. In vitro subculture to 100 generations,as the virus generation increased,its adaptability to cells continued to increase.The cell shedding time was gradually shortened from 48 to 17 h after virus infected.The virus titer was gradually increased from 10^5.3TCID₅₀/mL at the 6th generation to 10^7.5TCID₅₀/mL at the 100th generation.The virulence test showed that the virulence of the virus gradually decreased with the increase of the generation,and the 40th generation had no pathogenicity to the piglets.This article built the foundation for the identification of the pathogenic genes and the development of vaccines of PEDV mutants.

To obtain and analyze highly purified porcine circovirus virus type 2 (PCV2) virus-like particles(VLPs),the PCV2 recombinant Cap protein (PCV2 rCap) was expressed by Escherichia coli expression system,and was purified by the means of ammonium sulfate precipitation,gel filtration chromatography,ion exchange chromatography and CsCl density gradient centrifugation.The immunoreactivity of purified VLPs were identified by Western blotting,the diameter and morphology of purified VLPs were observed by transmission electron microscopy (TEM).Its components were detected and analyzed by high performance liquid size exclusion chromatography (HPSEC).After purification,the PCV2 rCap protein was detected by SDS-PAGE,the target protein band of 28 ku was detected,and its purity was 97.53% by gray scale scanning.The results of Western blotting showed that the specific protein strips had obvious immunoreactivity.The TEM detected the regular spherical particles with the particle size of 17.35 to 19.24 nm,indicating that the obtained PCV2 rCap protein could express itself in the bacteria.They were assembled into VLPs and deagglomerated without being destroyed during the purification process,and remained in a natural state;In addition,HPSEC detected that the proportion of normally assembled VLPs was 92.67%.The results of this study provided a reference for further study of the spatial structure of PCV2 VLPs and their immune protection mechanisms.

The aim of the experiment was to optimize the prokaryotic expression system of selenoprotein W (SelW),and evaluate the immunogenicity of SelW and the feasibility of detecting SelW in swine based on IgY antibodies.The obtained gene sequence codon of porcine SelW was optimized,synthesized and ligated into pET-32a(+) expression vector,and the prokaryotic expression recombinant plasmid pET32a(+)-SelW was constructed and transformed into E.coli BL21 host strain,which was induced by IPTG.The expression of SelW in recombinant swine was identified by SDS-PAGE,and the IgY polyclonal antibody against SelW was prepared by immunizing laying hens,the IgY antibody titer was detected by indirect ELISA,the specificity of the IgY recognition antigen was examined using Western blotting.The results of SDS-PAGE showed that SelW gene was successfully expressed in prokaryotic cells,and a recombinant protein with a size of about 33 ku was obtained.The optimal expression concentration and time of IPTG were 0.5 mmol/L and 6 h,respectively.Soluble analysis results showed that the recombinant protein existed mainly in the form of inclusion bodies.The results of indirect ELISA showed that the titer of IgY polyclonal antibody at 45 days after immunization could reach 1:51 200.Western blotting results showed that the recombinant protein had good immunogenicity,and the prepared IgY antibody had higher affinity with SelW.This experiment successfully constructed and optimized the prokaryotic expression system of SelW,increased the expression of SelW,and obtained SelW with good immunogenicity,and the prepared IgY antibody specifically recognized SelW in swine muscle tissue,which could be used to detect the expression of SelW in swine tissues.By measuring the expression of SelW to reflect the level of selenium in swine,it could be used to prevent selenium poisoning and selenium-deficient disease monitoring,and laid a foundation for further exploration of SelW biological function.

The test was aimed to express the L1 capsid protein of bovine papillomavirus (BPV),and prepare its polyclonal antibodies.Histopathological examination was conducted using the cutaneous papilloma samples of cattle.The L1 gene degenerate primer FAP59/FAP64 was used for amplification,and then specific primers were designed.The capsid protein L1 gene was subcloned into pET-30a(+) expression vector to construct recombinant prokaryotic expression vector pET30a-BPV2-L1.The recombinant protein rBPV2-L1 was expressed in E.coli Rosetta^TM(DE3)pLysS host strain,and the rabbit anti-BPV2-L1 protein polyclonal antibody was prepared by using purified rBPV2-L1 protein as immunogen,and then the titer was detected by indirect ELISA,indirect immunofluorescence assay was performed.The pathological tissue section observation showed that the epidermal cells proliferated,the keratin was excessive,and the tissue lesions of BPV infection such as cell hollowing occurred.Sequence analysis confirmed that the genotype of the BPV isolated strain was type 2,and the coding region of L1 gene was 1 494 bp,which could encode a capsid protein containing 497 amino acids with a molecular mass of 55.5 ku.Phylogenetic tree analysis with L1 amino acid sequence of each type of BPV showed that it was in the same genetic evolution branch as BPV2-SW01 (GenBank accession No.:KC878306.1) and BPV2 (GenBank accession No.:KX113620.1),and belonged to the genus Delta.The induced expression of rBPV2-L1 protein was mainly present in the precipitate in the form of inclusion bodies.The indirect ELISA assay results showed that the polyclonal antibody titer was as high as 1:163 840.Indirect immunofluorescence analysis results showed that the rabbit anti-BPV2-L1 polyclonal antibody reacted specifically with the transiently expressed BPV2-L1 protein.The above results confirmed that the BPV2 L1 gene was successfully cloned and expressed in this study,and the recombinant protein rBPV2-L1 had good immunogenicity.The prepared polyclonal antibody against BPV2-L1 protein had good immunological activity,and laid the foundation for further study of the BPV2 subunit vaccine.

In order to analyze the drug resistance of Klebsiella pneumoniae isolated from yak in Sichuan area,43 Klebsiella pneumoniae were isolated from 127 samples of lung,pharynx and nose swabs of yaks suffering from respiratory diseases in different feeding farms in Sichuan province.Microdilution broth method and PCR method were used to detect drug resistance and resistance genes of 43 strains of Klebsiella pneumoniae.The results showed that 43 strains of Klebsiella pneumoniae were resistant to ampicillin,amoxicillin,doxycycline and sulfamonomethoxine 4 drugs with a high resistance rate of 65.12% to 90.70%;The resistance rate to amikacin,florfenicol,polymyxin B and spectinomycin were 20.93% to 48.84%:And that to cefotafur,enrofloxacin,ciprofloxacin were 18.60% and 25.58%.Most isolates were multidrug resistant and 9 and 10 drug resistant strains accounted for 23.3% and 20.9%,respectively.The detection rates of bla_TEM,bla_SHV,sul2,sul3 and floR genes were high,ranging from 62.8% to 69.8%;The detection rates of ant(3″)-Ⅰa、aph(3')-Ⅱa,aac(6')-Ⅰb,aacC2 gene were low,ranging from 7.0% to 20.9%,and bla_CTX-M,Mcr-1,qnrA,qnrS,rmtB genes were not detected.In conclusion,Klebsiella pneumoniae isolates in this experiment had strong drug resistance and carried multiple drug resistance genes.And in order to better promote the development of yak breeding industry in Sichuan province,more attention should be paid to avoid the abuse of antibiotics through drug sensitivity test.

This experiment was aimed to study the relative expression of NF-κB and the tight junction protein(occludin,claudin-1 and ZO-1) mRNA and the changes of villus length (V),crypt depth (C) and V/C value in the development of broiler ascites syndrome,providing a theoretical basis for the prevention and treatment of broiler ascites syndrome.A total of 40 1-day-old Ross broilers were routinely reared for 7 days and randomly divided into control group and model group (added 3% lard and 4% fish meal to standard,added 0.12% NaCl to drinking water,and raising temperature at 9-11℃),and measured body weight at 35 days old.The ascites heart index was measured,and the jejunum tissue was taken for HE staining to measure the villus length and crypt depth.The gene expression of jejunal NF-κB and tight junction protein were detected by Real-time PCR.The results showed that compared with control group,the weight of broiler in model group was extremely significantly decreased (P<0.01),the ascites heart index was extremely significantly increased (P<0.01),the jejunum length and V/C value were extremely significantly decreased (P<0.01),the crypt depth was extremely significantly increased (P<0.01),the relative expression of NF-κB mRNA was extremely significantly increased (P<0.01),and the relative expression of tight junction proteins occludin,claudin-1 and ZO-1 mRNA were extremely significantly decreased (P<0.01).This results indicated that the intestinal mucosal structure and function abnormality and intestinal permeability increase promoted the development of broiler ascites syndrome.

The trial was designed to identify pathogens infected with Pelteobagrus fulvidraco and explore their resistance.The bacteria were isolated and identified by bacterial culture,physiological and biochemical identification and 16S rDNA sequence analysis.PCR method was used to amplify drug resistance genes.The resistance of drugs was detected by agar disk diffusion test.The results showed that the isolate was basically identical to Pseudomonas mendocina,and the 16S rDNA gene was 1 442 bp in length.Homology and phylogenetic tree analysis showed that the 16S rDNA sequence of this bacterium was 99.6% homologous to Pseudomonas mendocina NK-01,and their genetic relationship was the closest.The isolated strain was identified to be Pseudomonas mendocina,named as fsznc-01.The results of drug resistance gene test showed that the isolate fsznc-01 contained β-lactams resistance gene TEM,aminoglycosides resistance genes aph(3')-Ⅱa,aac(6)-Ⅰb and aac(3)-Ⅱa,and the sulfonamide resistance genes Sul1 and Sul2,and sulfonamide resistance genes Sul3 was not detected.The results of drug susceptibility test showed that the isolate fsznc-01 was sensitive to ceftazidime,gentamicin and piperacillin,and was resistant to cephalexin,cefazolin and cefradine.The results of this test could provide a reference for the prevention of fish diseases caused by Pseudomonas mendocina infection.

The aim of this study was to investigate the effects of Staphylococcus aureus (S.aureus) and Escherichia coli (E.coli) on the expression of cytokines interleukin-6 (IL-6),IL-1β and IL-8 and damage of dairy cow endometrial tissues.The in vitro cultured dairy cow endometrium tissue was used as the research object,and was infected in vitro with E.coli and S.aureus at a concentration of 1×10⁵ to 1×10⁹ CFU/mL.Real-time PCR and ELISA were used to detect the expression of IL-6,IL-1β and IL-8 mRNA and protein in dairy cows endometrium tissue after two kinds of bacteria stimulation,and the dairy cows endometrial histopathology sections were observed by HE staining.The results showed that the expression of IL-6,IL-1β and IL-8 mRNA in dairy cows endometrium tissue was extremely significantly higher than that in the blank control group after E.coli infection at a concentration of 1×10⁵ to 1×10⁹ CFU/mL (P<0.01).When the concentration of S.aureus infection was 1×10⁵ and 1×10⁶ CFU/mL,the expression of IL-6 and IL-1β mRNA was extremely significantly higher than that of the blank control group (P<0.01);The infection concentration was 1×10⁷ CFU/mL,the expression of IL-6 and IL-1β mRNA was significantly higher than that in the blank control group (P<0.05);The infection concentration was 1×10⁶ CFU/mL,the expression of IL-8 mRNA was significantly higher than that in the blank control group (P<0.05);Other infection concentrations were not significantly different from the blank control group (P>0.05).The expression levels of IL-6,IL-1β and IL-8 were significantly higher in the dairy cows endometrial tissues infection with 1×10⁵ to 1×10⁹ CFU/mL S.aureus and E.coli (P<0.01).The expression of IL-6,IL-1β and IL-8 mRNA and protein in the dairy cows endometrial tissues infected with E.coli at the same concentration was extremely significantly higher than those in the S.aureus infection group (P<0.01).The results of HE section staining showed that some epithelial cells remained after E.coli infection,while epithelial cells all fell off after S.aureus infection.The results of this test showed that the inflammatory response caused by E.coli and S.aureus infected with endometrial tissue of cows was different.After E.coli infection,pro-inflammatory cytokines were significantly up-regulated,while S.aureus infection destroyed endometrial epithelial cells to a greater extent.

In order to study the epidemiological characteristics and drug resistance of HPI gene of E.coli,feces and anal swabs were collected from Chuxiong local pig farms in Yunnan province.The isolation and identification of E.coli were carried out by McConkay medium,biochemical identification tube and PCR amplification.The HPI gene carrying status,pathogenicity and drug resistance of the isolates were studied by PCR reaction,animal regression test and disk diffusion method respectively.The results showed that 78 strains of E.coli were isolated,the isolation rate was 83.87%,and the carrying rate of HPI gene was 96.15%.Within 24 h,the mortality rate of HPI-positive strains was 100%,and that of HPI-negative strains was 75%.No mice died in the control group,suggesting that HPI gene could increase the mortality rate of mice.Drug susceptibility tests showed that the drug resistance rates to tetracycline,ampicillin,compound sinomenine,kanamycin,gentamicin,ceftazidime and amikacin were 88.46%,84.62%,73.08%,53.85%,38.46%,19.23% and 5.13%,respectively.Colistin B showed no drug resistance.The results showed that the epidemic situation of HPI gene in Chuxiong prefecture of Yunnan province was optimistic,and it could provide a theoretical basis for the prevention and treatment of E.coli-related diseases.

To ascertain the cause of the death of nursery pigs in Yangjiang city,Guangdong province,we carried out the bacteriological and drug sensitive test of 3 clinical samples (lung,liver and spleen) collected from pigs in this study.PCR/RT-PCR method were used to test pseudorabies virus (PRV),classical swine fever virus (CSFV),porcine reproductive and respiratory syndrome virus (PRRSV),circovirus type 2 (PCV2),circovirus type 3 (PCV3) and Mycoplasma hyopneumoniae in clinical samples.Futhermore,the nucleotide sequence of PRRSV ORF5 gene from three positive samples was determined,which conducted nucleotide sequence similarity analysis and constructed genetic evolution tree with VR2332,HuN4,JXA1,CH-1a and other representative strains.It indicated that a strain of Haemophilias paresis (Hps) was isolated and identified by bacteriological detection.Hps had strong sensitivity to 7 kinds of clinical drugs,such as amoxicilin and cefradine.The gene similarity analysis showed that the PRRSV ORF5 gene nucleotide similarity in three strains (LJW1,LJW2 and LJW3) was 99.3% to 99.8%,the nucleotide similarity to the European-type representative strain Lelystad was 64.0% to 64.2%,the nucleotide similarity with HP-PRRSV strains JXA1,HuN4,CH-1a and TJ were 99.2% to 99.5%,99.0% to 99.3%,94.5% to 94.9%,98.8% to 99.2%,respectively;The higher nucleotides similarity contrast with HP-PRRSV strains HeNzm1-16 and GXL205-2015 isolated from Henan and Guangxi in China were 99.3% to 99.7% and 99.2% to 99.7%,respectively.The nucleotide similarity with the American classic vaccine strains MLV,the American standard strains NC,and the American classic strain VR-2332 was 88.5% to 88.8%,85.2% to 85.5% and 82.3% to 82.6%,respectively.The phylogenetic tree analysis of PRRSV ORF5 showed that all the three strains belonged to the American strain,and they were in the same branch with the domestic HP-PRRSV representative strains JXA1,HuN4,TJ,etc,and the genetic relationship was the closer.This study revealed the pathogens of pigs in this field,and confirmed the genetic relationship between three isolates from PRRSV and different representative strains at the molecular level,which provided a basis of the rational selection and use of attenuated vaccines and comprehensive prevention and control PRRSV.

Some toxic and harmful substances can lead to huge risks of food safety such as pathogenic microorganisms,biotoxins,pesticides,veterinary drugs and additives residues.Nowadays,monitoring of toxic and hazardous substances still faces enormous challenges.Metabolomics techniques detect metabolically changes in organisms which are stimulated or interfered by toxic and hazardous substances,then it will perform qualitative and quantitative analysis of the data and obtain highly sensitive and specific metabolomics projection,which makes it suitable for simultaneous monitoring of different trace toxicants.Metabolomics technology can reflect possible biomarkers in the process of toxicant metabolism,and provide references for further researches on toxic metabolic processes and toxicological mechanisms.Therefore,the metabolomics method represented by chromatographic mass spectrometry,nuclear magnetic resonance and other methods has gradually become a key technology for the detection of toxic and hazardous substances,and it provides a basis for risk assessment of toxic and hazardous substances.The discovery of various biomarkers and the optimization of detection methods will promote the practical application of metabolomics technology in simultaneous monitoring of toxicant.The generation and development of metabolomics technology were introduced,and the researches of metabonomics methods and biomarkers of metabolites were summarized in this paper in order to provide references for the further application of metabolomics technology in the detection of toxic and harmful substances.

With the development of society and the transformation of production mode,the labor function of donkey has gradually disappeared,and turned to meat production leading to rapid development of donkey industry in recent years.The present study reviewed the effect factors on nutritional characteristics and meat quality of donkey such as breed,age,feed nutrition,slaughter and processing,and identification.Previous studies had shown that donkey meat had three high three low characteristics,which were high protein,high essential amino acids,high unsaturated fatty acids and low fat,low cholesterol,low calories,and was considered as a high quality protein source.The protein and fat content of donkey meat were affected by breed and slaughter age.The supplementation of plant extracts could increase the feed digestibility and improve the meat quality of donkey.The nutritional content of donkey meat in different parts were different,which the edible quality of the longissimus dorsi was higher than that of the buttock meat comparison of protein,fat,shear force and cooked meat rate.Electric stimulation could improve the tenderness of donkey meat through accelerating the acid removal process,changing the muscle fiber structure and promoting calpain degradation.Fourier transform infrared spectroscopy could be used for discrimination of donkey meat.The authors summarized the influencing factors of donkey meat quality and nutritional value in order to provide references for the standards of donkey meat production and guarantee donkey meat quality.